Health and Safety ReportVolume 20, Issue 2

On Topic

The Air You Breathe: Improving Workplace Ventilation print this article

Delano has started a new job as a bicycle mechanic this winter. He works alongside two other mechanics at the back of a bike shop. The work area has plenty of space, but Delano knows that the risk of COVID-19 spread is increased when people from different households gather in enclosed spaces and are in close contact.

Delano and his colleagues wear masks, but that’s only one layer of protection. He wonders if the ventilation in the space is sufficient to keep the workplace safe. There are windows but it has been too cold outside to open them. He wonders if there is any fresh air being brought into the shop and if the warm air coming from the ducts is filtered.

Indoor ventilation is a critical control measure. Employers should understand how it affects the spread of COVID-19 and make sure that they have a properly ventilated workplace.

Ventilation is a critical control measure

Ventilation is the process of supplying air to or removing air from a space to help control air contaminant levels. In spaces where there is effective ventilation, the concentration of contaminants (including viruses) in the air is diluted by allowing clean outside air into a space and removing potentially contaminated air.

The virus that causes COVID-19 spreads from an infected person through the air by respiratory particles that are released when that person breathes, talks, shouts, coughs, or sneezes. Indoors, the accumulation of COVID-19 viruses depends upon the ventilation rate, humidity, air mixing patterns, room size, number of infected occupants, and the amount of virus they are releasing.

Maximize indoor ventilation

There are two types of ventilation, natural and mechanical, and both should be maximized in indoor workspaces. Natural ventilation allows outside air into and inside air out of a space by opening exterior windows and doors. Mechanical ventilation is most often provided by Heating, Ventilation and Air Conditioning (HVAC) systems. HVAC systems circulate conditioned air within a space with motor-driven fans or blowers through ducts. Recirculating stale air within a space using pedestal fans, ceiling fans or ductless air conditioners, is not ventilation.

Improving ventilation is one layer of protection for the occupants of a space. HVAC systems are complex so it’s important to consult with an HVAC professional before making any changes or improvements. Questions to ask include:

  • Is the ventilation system inspected and maintained regularly?
  • Have filters been replaced as recommended?
  • Do the filters have the highest possible Minimum Efficiency Reporting Value (MERV) ratings recommended for use with the system?
  • Has the system been set to the maximum air changes per hour?

To maintain an effective HVAC system, use HVAC system filters with the highest rated MERV filters  and are compatible with your ventilation system.

Set the ventilation rate to the highest setting possible that the system can handle. It’s a good idea to run ventilation systems continuously. Adjusting the system to maximize outdoor air intake will provide more air dilution in a space.

Open windows and doors to allow outside air in, as weather permits and if it’s safe to do so. Allowing outside air in, even for a few minutes at a time throughout the day, can improve ventilation with minimal impact on indoor temperature and humidity. If outside air is of low quality – due to pollen or for instance - it may be necessary to minimize its intake into a building or pre-filter the air as it enters the building.

Simple steps such as continuously running local exhaust fans in washrooms, kitchens, and break rooms can also improve indoor air quality.

Maintain mechanical ventilation systems

Properly designed and functioning HVAC systems keep indoor air circulating.

Make sure that your ventilating systems are properly rated and configured for the layout of the space, type of activity, and maximum occupancy. Avoid directing airflow from person to person. Adjust air supply vents and fans, if necessary. Schedule regular inspections and maintenance including filter and parts replacements to keep the system running effectively.

In work areas where there is no natural or mechanical ventilation, the use of portable air cleaners with HEPA filters are an option to help improve air quality. It should be noted that they are not as effective as a properly functioning HVAC system and have not specifically been proven to be effective against the virus that causes COVID-19.

Back at the bike shop, Delano shares his indoor air quality concerns to his supervisor who tells him that the store and workshop’s HVAC system has been designed for the space and is serviced regularly by a certified technician. In the summer, there is air conditioning, and they usually open the windows when the weather is good.


CCOHS Resources

Need help with a workplace health and safety issue? Contact our Safety Infoline


New Courses on Creating Psychologically Healthy and Safe Workplacesprint this article

Worker mental health can be affected by work-life balance, clearly defined roles and responsibilities, and other factors. CCOHS has released two online courses to help both workers and employers gain a deeper understanding of the roles and factors in creating a psychologically safe workplace.

Psychological Health and Safety for Workers

People in Canada spend a significant amount of time in the workplace, making its potential impact on our mental health substantial.

Learn how to define psychological health and safety and how your work environment affects mental health. You will also identify factors that influence mental health and understand both your role and your employer’s role in promoting psychological health and safety in your workplace.

This course is free until March 31, 2022. Take the course here.

Psychological Health and Safety for Employers

Understand your role as an employer in creating a psychologically healthy and safe environment.

Learn how to recognize why psychological health and safety is important, gain support for psychological health initiatives across your organization, and assess the psychological health and safety of your workplace. You’ll gain insights on how to create an environment where your workers feel supported, and how to apply control measures to improve the psychological health and safety of your workplace.

Register here.

Additional mental health courses from CCOHS:

New COVID-19 Resources

COVID-19 Resources: Vaccination Policies and Reducing Return Anxiety print this article

As the COVID-19 pandemic evolves, CCOHS continues to release new and updated resources to help keep workplaces operating safely. With mandates lifting in some parts of the country, many businesses are considering a return to the workplace, either full-time or in a hybrid capacity. Either way, it’s important to incorporate COVID-19 control measures into your health and safety plans. Get free guidance to protect your workers and customers and reduce the risks of COVID-19 in your workplace.

New and updated COVID-19 tip sheets include:

View our full collection of tip sheets, infographics, videos, and other guidance. You can also download our free COVID-19 resources app here.


Keeping Up with New Legislationprint this article

Occupational health and safety laws are always evolving. This month’s highlights include two new federal regulations, amendments to  Occupational Health and Safety Regulations in Northwest Territories, amendments to the Workplace Safety and Insurance Act in Ontario, and new Offshore Area Occupational Health and Safety Regulations in Newfoundland.


Two new federal regulations came into force 01/01/22: 1) the Canada–Newfoundland and Labrador Offshore Area Occupational Health and Safety Regulations (SOR/2021-247), which also make amendments to the Newfoundland Offshore Certificate of Fitness Regulations (SOR/95-100); and, 2) the Canada–Nova Scotia Offshore Area Occupational Health and Safety Regulations: (SOR/2021-248), which also make amendments to the Nova Scotia Offshore Certificate of Fitness Regulations (SOR/95-187).

Northwest Territories

The Occupational Health and Safety Regulations (Safety Act): R-074-2021 amends the minimum load capacity values with respect to personal fall arrest and travel restraint systems, corrects a reference to tower hoists, introduces new appendices defining chemical and biological substances and listing contamination limits, and makes numerous grammatical adjustments to the French version of the legislation.


Workplace Safety and Insurance Act, 1997: S.O. 2021, c. 35, Sched. 6 came into force 01/01/22 and makes amendments with respect to the insurance fund.  Section 96.1 Plan, sufficiency of fund of the Act and subsection 97 (2) of the Act are repealed. New Section 97.1 Distribution of surplus provides that, in certain circumstances, the Board is permitted or required to distribute amounts in the insurance fund in excess of specified amounts among Schedule 1 employers. New section 97.2 No right of reconsideration or appeal, provides that a determination made by the Board under section 97.1 cannot be reconsidered by, or appealed to, the Board or the Tribunal. Related regulation making authorities are added to section 100.  Section 159 of the Act is amended to provide that the Board may enter into an agreement with any person or entity for the purpose of administering Part VII (Employers and their Obligations).


New regulations, the Offshore Area Occupational Health and Safety Regulations (N.L.R. 79/21) came into force 01/01/22.

For more information regarding recent regulatory changes CCOHS offers a paid subscription service, Canadian enviroOSH Legislation plus Standards, that provides a collection of all the health, safety, and environmental legislation you need in one location.


Free Webinars on Preventing Workplace Harassment and Violence print this article

Are you involved in developing a workplace harassment and violence policy? For federally regulated workplaces, having one in place is a requirement under the Canada Labour Code Part II

CCOHS is hosting two webinars to help you understand everyone’s roles and responsibilities, and the necessary parts of a prevention policy. You’ll also learn how to respond to an occurrence and communication techniques that promote safe interactions through civility and respect. These 45-minute sessions will help both those in federally regulated workplaces and anyone interested in the prevention of workplace harassment and violence. Each session includes a presentation and question and answer period (live in English, pre-recorded in French).

March 9: Preventing Workplace Harassment and Violence Part 1: Roles, Responsibilities and Responding


March 10: Preventing Workplace Harassment and Violence Part 2: Civility, Respect and Communication



Sitting at Workprint this article

CCOHS releases new podcasts each month to help you stay current and informed on workplace health, safety, and well-being in Canada.

New Podcast: Sitting at Work

Work that involves sitting is not without risk of injury. In fact, varicose veins, stiff necks, and numbness in the legs are reported more frequently among seated employees than those doing heavier tasks. Limited mobility contributes to injuries in the parts of the body that move us: the muscles, bones, tendons and ligaments.

In this episode, we discuss how to recognize and prevent injuries while sitting at work.

Podcast runs: 6:10  Listen Now

Encore Podcast: Tips to Help Raise the Awareness in RSI Day

International Repetitive Strain Injury (RSI) Awareness Day is February 29th. As the only non-repetitive day of the year, it’s the ideal date to devote to raising awareness of repetitive strain injuries. Listen for tips to help identify the risk factors and avoid the patterns that can lead to these injuries.

Podcast runs: 3:26 Listen Now

See the complete list of podcast topics or, better yet, subscribe to the series on iTunes or Spotify and don't miss a single episode.

Share Your Story

Share Your Workplace Health and Safety Impact Storyprint this article

Share your story about how you have used CCOHS resources and services to help make a positive impact on health and safety in your workplace. 

In return for your story, you’ll be entered into a draw to win a $100 Indigo gift card.

The survey is open until 5 pm EST March 24, 2022.

Last Word....

Resources for Repetitive Strain Injury Awareness Dayprint this article

As the only non-repeating day of the year, February 29th (and on non-leap years, February 28th) is the perfect day to raise awareness of RSIs.

Also known as musculoskeletal disorders (MSDs), RSIs are an umbrella term used to describe a family of painful disorders affecting tendons, muscles, nerves and joints in the neck, upper and lower back, chest, shoulders, arms and hands.

CCOHS has created a number of resources to help raise awareness of RSIs in your workplace, whether remote, in-person or hybrid.

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